• Journal of the Korea Institute of Information and Communication Engineering
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• v.25 no.11
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• pp.1635-1641
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• 2021

Portable systems with built-in active noise control is required low power operation. Excessive anti noise search operation can lead to rapid battery consumption. A method that can adaptively cancel noise according to the operating conditions of the system is required and the methods of reducing power are becoming very important key feature in today's portable systems. In this paper, we propose the method of active noise control(ANC) using binary search algorithm in noisy systems. The implemented architecture detects a frequency component considered as noise from the input signal and by using the binary search algorithm, the system find out an appropriate amplitude value for anti-noise in a much faster time than the general linear search algorithm. Through the experimental results, it was confirmed that the proposed algorithm performs a successful functional operation.

• Journal of the Korea Society of Computer and Information
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• v.24 no.10
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• pp.91-99
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• 2019

In this paper, we propose partial denoising boundary matching based on an index for faster matching in very large image databases. Attempts have recently been made to convert boundary images to time-series with the objective of solving the partial denoising problem in boundary matching. In this paper, we deal with the disk I/O overhead problem of boundary matching to support partial denoising in a large image database. Although the solution to the problem superficially appears trivial as it only applies indexing techniques to boundary matching, it is not trivial since multiple indexes are required for every possible denoising parameters. Our solution is an efficient index-based approach to partial denoising using $R^*-tree$ in boundary matching. The results of experiments conducted show that our index-based matching methods improve search performance by orders of magnitude.

• Journal of the Korean Society of Radiology
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• v.13 no.4
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• pp.623-628
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• 2019

The aim of this study was to design fast non local means (FNLM) noise reduction algorithm and to confirm its application feasibility in light microscopic image. For that aim, we acquired mouse first molar image and compared between previous widely used noise reduction algorithm and our proposed FNLM algorithm in acquired light microscopic image. Contrast to noise ratio, coefficient of variation, and no reference-based evaluation parameter such as natural image quality evaluator (NIQE) and blind/referenceless image spatial quality evaluator (BRISQUE) were used in this study. According to the result, our proposed FNLM noise reduction algorithm can achieve excellent result in all evaluation parameters. In particular, it was confirmed that the NIQE and BRISQUE evaluation parameters for analyzing the overall morphologcal image of the tooth were 1.14 and 1.12 times better than the original image, respectively. In conclusion, we demonstrated the usefulness and feasibility of FNLM noise reduction algorithm in light microscopic image of small animal tooth.

• Korean Journal of Optics and Photonics
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• v.21 no.1
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• pp.21-25
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• 2010

In this paper, in order to enhance the image reconstruction performance of white light scanning interferometry(WLI), we demonstrate the scattered point noise filtering performance of post-processing methods. Median filtering is similar to using an averaging filter. Because the median value is less sensitive than the mean to extreme values, the median filter can remove the scattered point noise from a height-map without significantly reducing the sharpness of the image. In several specific cases, however, the median filter can't remove the scattered point noise. Therefore, we propose a comparative mean filter that uses order-statistic filtering and the mean of the neighborhood pixels. The performance is demonstrated by measuring an array of metal solder balls fabricated on PCB. The proposed method reduced the noise pixels by 4.4 percent.

• Journal of the Korean Society of Radiology
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• v.7 no.3
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• pp.181-189
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• 2013

The optimum exposure parameters are found when examined using the automatic mode in FFDM. improve the image quality by applying denoising algorithm and propose methods to reduce AGD(Average Grandular Dose) a patient can receive. For the experiment, Nuclear Associates Model 18-222 phantom was the used, and the entrance dose and AGD were measured. And then, Signal, Noise, SNR and FOM(Figure of Merit) were measured, compared and analyzed image denoising before and after. As the experiment result, first, SNR was the highest at Mo/Mo 23kVp and W/Rh 35kvp was the lowest for the average glandular dose. It showed to use 28kVp of W/Rh to be the best through the result of FOM. SNR was the highest at Mo/Mo 23kVp(image denoising), and it showed to W/Rh and 28kVp to be the best in the FOM result which AGD was considered at the same time. By the image denoising, it is possible to reduce noise while maintain important information in the image.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.1483-1484
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• 2015

부분방전 진단 기술 분야에서는 노이즈의 영향을 최소화할 수 있는 기법이 요구되고 있는 실정이다. 본 논문에서는 부분방전과 노이즈 신호 추출을 위한 로그앰프의 반응 속도차와 부분방전 신호특성을 비교하여 노이즈를 제거하는 SRPDA(Speed Related Partial Discharge Analysis)를 적용한 부분방전 진단 시스템의 개발 내용을 나타내었다. 또한 본 시스템은 광대역 방식의 장점인 빠른 검출 속도와 협대역 방식의 장점인 적은 노이즈의 영향의 장점을 취하는 동시에, 광대역 방식의 단점인 큰 노이즈 영향과 협대역 방식의 단점인 느린 진단 속도를 개선할 수 있는 하이브리드 방식을 채택하여, 기존 부분방전 진단 시스템의 신뢰성을 개선할 수 있을 것으로 사료된다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.2
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• pp.183-190
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• 2013

In this paper, we propose a spatially adaptive noise detection and removal algorithm for a single degraded image. Under the assumption that an observed image is Gaussian-distributed, the noise information is estimated by local statistics of degraded image, and the degree of the additive noise is detected by the local statistics of the estimated noise. In addition, we describe a noise removal method taking a modified Gaussian filter which is adaptively determined by filter parameters and window size. The experimental results demonstrate the capability of the proposed algorithm.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.45 no.2
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• pp.74-80
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• 2008

Spatio-temporal filters are capable of reducing noise from moving pictures, which cannot be dealt with by spatial filters. However, the algorithm is too complicated to be realized as hardware. We implemented a real-time spatio-temporal noise reduction system, using at most three frames, based upon adaptive mean filter algorithm. Some factors which interfere with hardware implementation were modified. Noise estimated from the previous frame was used to filter the current frame so that filtering could be conducted in parallel with noise estimation. This speeds up the system thereby enabling real-time execution. The form of filtering windows was also modified to facilitate synchronization. The proposed structure was implemented on Virtex 4 XC4VLX60, occupying 66% of total slices with 80MHz of the maximum operation frequency.

• Journal of Korea Technology Innovation Society
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• v.15 no.1
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• pp.105-128
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• 2012

This paper proposes the technological level assessment which improved reliability and the efficient noise elimination methods in the process of establishing patent map analysis data. In order to eliminate efficiently noise (removed by the manual process in the past), the paper applies the Logical Operator 'AND', makes it a program in excel VBA(Visual Basic Application), and obtains the valid data. For the improved reliability technological level assessment of the patents, the study calculates average number of claims, Patent Family Size(PFS), Cites Per Patent (CPP), Triad Patent Families, Standardization Patent Diversification Index (stdPCPI), and haF-index(Hirsch a Family index). The result which applied noise exclusion work showed less than 10% of acquired patent data ratio and confirmed high reliability. The result that apply proposed technological level assessment index makes sure that balanced technological level assessment which improved reliability by producing synthetic technological level assessment.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2010.11a
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• pp.125-126
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• 2010

채널의 다중경로를 통과한 신호들은 지연확산 영향으로 심하게 왜곡이 되거나 Inter-Symbol Interference(ISI)가 발생하므로 왜곡된 채널을 추정하여 보상해야 한다. 기존 iterative 채널 추정 방식에서는 채널 시간 지연 길이 밖으로 zero padding함으로 노이즈 성분을 제거하는 알고리즘이다. 반면에 본 논문은 채널 시간 지연 길이 안으로 있는 노이즈 성분까지 노이즈 제거 문턱 값 추정(noise elimination threshold estimation: NETE) 알고리즘을 사용하여 노이즈를 효과적으로 제거한다. 시뮬레이션 결과는 채널의 mean square error(MSE)를 통하여 제안된 기법을 적용할 경우 채널 추정 성능 개선이 나타남을 확인할 수 있었다.